Abstract

The effect on performance of variations in power plant, aircraft, and rocket parameters was calculated for a lifting air breathing boost system for launching satellites. A limited variation in aircraft flight plan was considered also. In addition, comparisons were made between the air breathing boost system and a three stage all rocket system. For the air breathing boost computations were made for launch Mach numbers ranging from two to five.

The air breathing boost was assumed to be a turbojet or dual cycle engine powered aircraft. The rocket used in conjunction with the boost had two stages. In computing aircraft performance thrust and engine specific fuel consumption were taken as constants. The lift to drag ratio was also considered constant for each portion of the flight profile which consisted of a take off and acceleration to climb speed, a two step climb, and a pull up to the maximum angle attainable for rocket launch.

In computing rocket performance burning times, effective exhaust velocities, payload weight ratios, and structural weight ratios were assumed to be the same for each stage. Drag was neglected in rocket calculations, and the acceleration of gravity was assumed constant. The calculations were made by computing the kinetic and potential energies for a sounding rocket and equating them to the energy required for orbit.